If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

For genus and species by monotypy. Characters derived from the original diagnosis of You, Luo, et al. (2003) are marked with an asterisk (*). Basal hadrosauroid characterized by four autapomorphies: (1), rostrodorsally curved finger-like process that arises from the maxillary process of the jugal at the jugal-lacrimal contact*; (2), elongate rostral ramus of lacrimal that extends along the dorsal margin of the maxilla and terminates rostral to the apex of the ascending process of the maxilla*; (3), epipophyses present on third cervical vertebra; and (4), hyposphene present on at least dorsal vertebrae 6–8 and 11–15. Also distinguished by the following unique combination of characters: rostral ramus of lacrimal tapers to a point, ventrolateral process of premaxilla contacts prefrontal (also noted by Paul, 2008:201, as lack of contact between the lacrimal and nasal); quadrate gradually curves caudally along its entire length in lateral view (also noted by Paul, 2008:201, as “shaft nearly straight”); and convex dorsal margin of ilium (also noted by Carpenter and Ishida, 2010).